fractions

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fractions

by vladmire » Wed Jan 07, 2009 6:31 pm
How do you solve a power when its a fraction?

(8)^2/3 = ?

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by cramya » Wed Jan 07, 2009 6:35 pm
This is nothing but

cuberoot(8^2) = 4

Consider sqrt(4) = 4 ^ 1/2 = squarroot(4^1)

We did the same thing above


Hope this helps!

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by pandeyvineet24 » Wed Jan 07, 2009 9:55 pm
yep do a square of 8 and take its cube root.

cuberoot(8 * 8) = 4

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fractions

by welcome » Thu Jan 08, 2009 6:40 am
(8)^2/3 = (2^3)^2/3 = ((2^3)^1/3)^2 = 2^2 = 4

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Re: fractions

by Stuart@KaplanGMAT » Thu Jan 08, 2009 10:24 am
welcome wrote:(8)^2/3 = (2^3)^2/3 = ((2^3)^1/3)^2 = 2^2 = 4
Good solution, using the multiplication of exponents rule:

(x^a)^b = x^(a*b)

so:

8^(2/3) = (2^3)^(2/3) = 2^(3*2/3) = 2^2 = 4
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